0
via techrepublic
1. Nmap
2. Nessus Remote Security Scanner
3. John the Ripper
4. Nikto
5. SuperScan
6. p0f
7. Wireshark (Formely Ethereal)
8. Yersinia
9. Eraser
10. PuTTY
11. LCP
12. Cain and Abel
13. Kismet
14. NetStumbler
15. hping
via darknet